Quartz.NET is a powerful open-source job scheduling library for .NET applications. When combined with Topshelf, it enables the creation of robust Windows services capable of executing scheduled background tasks.

Project Setup

Create a new console application named QuartzJobDemo. The following components are required:

• Quartz.NET (version 2.x or 3.x)
• Topshelf
• Topshelf.Log4Net (matching Topshelf version)
• log4net for logging

Core Implementation

Scheduler Host: ServiceRunner.cs

using log4net;
using Quartz;
using Quartz.Impl;
using Topshelf;

namespace QuartzJobDemo.Services
{
    public sealed class ServiceRunner : ServiceControl, ServiceSuspend
    {
        private readonly IScheduler _scheduler;
        private readonly ILog _logger = LogManager.GetLogger(typeof(ServiceRunner));

        // For Quartz 2.x
        public ServiceRunner()
        {
            _scheduler = StdSchedulerFactory.GetDefaultScheduler();
        }

        // For Quartz 3.x (uncomment if upgrading)
        // public ServiceRunner()
        // {
        //     _scheduler = StdSchedulerFactory.GetDefaultScheduler().GetAwaiter().GetResult();
        // }

        public bool Start(HostControl hostControl)
        {
            _logger.InfoFormat("Service started at {0}", DateTime.Now);
            _scheduler.Start();
            return true;
        }

        public bool Stop(HostControl hostControl)
        {
            _logger.InfoFormat("Service stopped at {0}", DateTime.Now);
            _scheduler.Shutdown(waitForJobsToComplete: false);
            return true;
        }

        public bool Continue(HostControl hostControl)
        {
            _logger.InfoFormat("Service resumed at {0}", DateTime.Now);
            _scheduler.ResumeAll();
            return true;
        }

        public bool Pause(HostControl hostControl)
        {
            _logger.InfoFormat("Service paused at {0}", DateTime.Now);
            _scheduler.PauseAll();
            return true;
        }
    }
}

Job Implementation: TestJob.cs

using log4net;
using Quartz;
using System.Threading.Tasks;

namespace QuartzJobDemo
{
    public sealed class TestJob : IJob
    {
        private readonly ILog _logger = LogManager.GetLogger(typeof(TestJob));

        // Quartz 2.x: void Execute
        public void Execute(IJobExecutionContext context)
        {
            _logger.Info("Executing TestJob");
        }

        // Quartz 3.x: Task Execute (uncomment when upgrading)
        // public Task Execute(IJobExecutionContext context)
        // {
        //     _logger.Info("Executing TestJob");
        //     return Task.CompletedTask;
        // }
    }
}

Main Entry Point: Program.cs

using System.IO;
using log4net;
using QuartzJobDemo.Services;
using Topshelf;

namespace QuartzJobDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            var logConfig = new FileInfo(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "log4net.config"));
            log4net.Config.XmlConfigurator.ConfigureAndWatch(logConfig);

            HostFactory.Run(config =>
            {
                config.UseLog4Net();
                config.Service<ServiceRunner>();

                config.SetDescription("Quartz.NET Demo Service");
                config.SetDisplayName("QuartzJobDemo");
                config.SetServiceName("QuartzJobDemo");

                config.EnablePauseAndContinue();
            });
        }
    }
}

Configuration Files

Ensure the following configuration files are set to Copy Always in project properties.

log4net.config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
  </configSections>

  <log4net>
    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="D:\QuartzJobDemo_Log\servicelog\" />
      <appendToFile value="true" />
      <maxSizeRollBackups value="10" />
      <staticLogFileName value="false" />
      <datePattern value="yyyy-MM-dd".read.log"" />
      <rollingStyle value="Date" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%d [%t] %-5p %c - %m%n" />
      </layout>
    </appender>

    <appender name="ColoredConsoleAppender" type="log4net.Appender.ColoredConsoleAppender">
      <mapping>
        <level value="ERROR" />
        <foreColor value="Red, HighIntensity" />
      </mapping>
      <mapping>
        <level value="INFO" />
        <foreColor value="Green" />
      </mapping>
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%n%date{HH:mm:ss,fff} [%-5level] %m" />
      </layout>
      <filter type="log4net.Filter.LevelRangeFilter">
        <levelMin value="INFO" />
        <levelMax value="FATAL" />
      </filter>
    </appender>

    <root>
      <level value="ALL" />
      <appender-ref ref="ColoredConsoleAppender" />
      <appender-ref ref="RollingLogFileAppender" />
    </root>
  </log4net>
</configuration>

quartz.config

quartz.scheduler.instanceName = QuartzJobDemo

quartz.threadPool.type = Quartz.Simpl.SimpleThreadPool, Quartz
quartz.threadPool.threadCount = 10
quartz.threadPool.threadPriority = Normal

quartz.plugin.xml.type = Quartz.Plugin.Xml.XMLSchedulingDataProcessorPlugin, Quartz
quartz.plugin.xml.fileNames = ~/quartz_jobs.xml

quartz_jobs.xml

<?xml version="1.0" encoding="utf-8"?>
<job-scheduling-data 
    xmlns="http://quartznet.sourceforge.net/JobSchedulingData"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    version="2.0">

  <processing-directives>
    <overwrite-existing-data>true</overwrite-existing-data>
  </processing-directives>

  <schedule>
    <job>
      <name>TestJob</name>
      <group>TestGroup</group>
      <description>Sample recurring job</description>
      <job-type>QuartzJobDemo.TestJob, QuartzJobDemo</job-type>
      <durable>true</durable>
      <recover>false</recover>
    </job>
    <trigger>
      <cron>
        <name>TestTrigger</name>
        <group>TestGroup</group>
        <job-name>TestJob</job-name>
        <job-group>TestGroup</job-group>
        <start-time>2020-01-01T00:00:00+08:00</start-time>
        <cron-expression>0/5 * * * * ?</cron-expression> <!-- Every 5 seconds -->
      </cron>
    </trigger>
  </schedule>
</job-scheduling-data>

The cron expression 0/5 * * * * ? triggers the job every 5 seconds. Adjust as needed for production use.